The major theme of this proposed Superfund Hazardous Substances Basic Research Program is the elucidation of mechanisms of exposure and toxicity in humans and ecosystems to particular Superfund chemicals selected based upon their potential significance with respect to developmental effects. The major goals of the Program are as follows: 1) to elucidate mechanisms of developmental toxicity of selected Superfund chemicals and chemical mixtures; 2) to facilitate the transfer of mechanistic information obtained across selected invertebrate and vertebrate models relevant to human and/or ecological health; 3) to utilize microarray approaches for assessing gene expression during normal and perturbed development in our models, and enhance the genomic database for these models; 4) to develop highly sensitive and efficient markers for developmental toxicities that can be incorporated into human health and ecological assessments; 5) to elucidate microbial and photolytic transformations of selected Superfund chemicals that augment their environmental fate and effects upon development; 6) to use Geographic Information Systems (GIS) spatial analysis to develop and disseminate preventive risk models for environmental health in North Carolina, with an emphasis on children; 7) to effectively deliver the Program's research results to critical members of the scientific, governmental, business and lay communities;and 8) to enhance interdisciplinary research, and graduate and post-graduate training, in the biomedical and environmental sciences.